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sur le développement des zones arides et semi-arides

Titre : The effect of flood retention dams in Wadi Madoneh, Jordan on grondwater recharge

Auteur : Dissanayake, B.D.P.R.

Etablissement de soutenance : UNESCO-IHE Institute for Water Education, Delft

Grade : Master of Science (MS) 2010

Résumé
This research is carried out in the frame of the Dutch contribution to the multi-lateral Working Group onWater Resources, which was established in 1992 with the aim to enhance the cooperation between the Israeli, Jordanian and Palestinian authorities (known as the Core Parties) in the field of water. The activities of the Working Group are coordinated by the Steering Committee EXACT (Executive Action Team). The committee consists of representatives of the Core Parties and the donor countries (USA, EU, France, a.o.). In 2002 the government of The Netherlands decided to participate as a donor with the project : Small-scale water treatment facilities for domestic use and artificial recharge with surface water and UNESCO-IHE was asked to execute the project. Part of the Dutch project is a pilot study on artificial recharge in Jordan, comprising the construction of four flood retention dams in Wadi Madoneh, which catchment (34 km2) is situated in the desert, 15 km east of Amman. The aim of the retention structures is to enhance the infiltration of flood water in order to recharge the depleting groundwater reservoir. For this purpose the dams are designed such that the retained water is slowly released for infiltration in the wadi bed downstream of the dam. The hydrological study and the design of the dams were carried out by UNESCO-IHE and the dams were built by local contractor in the summer of 2007.The main objective of the study is to quantify the effect of the four flood retention dams on groundwater recharge. Specific objectives include establishing the rainfall-runoff relation for the catchment, showing the effect of the retention dams on this relation, estimating percolation and actual evapotranspiration using a simple Root Zone Model and developing a Routing Model to estimate the water table fluctuation from percolation. Relatively short series of data for rainfall, wadi and reservoir water levels, groundwater levels etc. were available to be used to achieve these objectives. Using these data, a Rainfall-Runoff relation was established and calibrated for the period prior to the construction of the flood retention dams.

Sujets  : groundwater recharge ; rainfall-runoff ; dams ; Jordan

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